As this train has GNWL from SBC to BZA/NGP/JBP/ALD/MGS/PNBE so many people who want to go till Bihar or U.P couldnot get seat from SBC or MAS as people travelling till BZA/NGP/JBP block these seats and then from there these seats run emptied. So if anyone needs instant Tickets in cas of Emergency for Bihar or U.P i would suggest u guys to book ur journey in two parts
1. From SBC to BZA/NELLORE/ONGOLE &
2. From there to JBP/ALD/MGS/PNBE
so...
more... i can tell u that there is 70% chance of getting ur tickets confirmed and that too at last momemt and DONT worry about GNWL from SBC to BZA/NELLORE/ONGOLE & RLWL from BZA to PNBE/ALD/MGS its always available after clearing all seats in waitinglist and i have constantly observed CURRENT AVAILABILITY is there.